diff options
Diffstat (limited to 'arch/csky/abiv2/strlen.S')
| -rw-r--r-- | arch/csky/abiv2/strlen.S | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/arch/csky/abiv2/strlen.S b/arch/csky/abiv2/strlen.S new file mode 100644 index 0000000000000..bcdd70764d086 --- /dev/null +++ b/arch/csky/abiv2/strlen.S @@ -0,0 +1,97 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include <linux/linkage.h> +#include "sysdep.h" + +ENTRY(strlen) + /* Check if the start addr is aligned. */ + mov r3, r0 + andi r1, r0, 3 + movi r2, 4 + movi r0, 0 + bnez r1, .L_start_not_aligned + + LABLE_ALIGN +.L_start_addr_aligned: + /* Check if all the bytes in the word are not zero. */ + ldw r1, (r3) + tstnbz r1 + bf .L_string_tail + + ldw r1, (r3, 4) + addi r0, 4 + tstnbz r1 + bf .L_string_tail + + ldw r1, (r3, 8) + addi r0, 4 + tstnbz r1 + bf .L_string_tail + + ldw r1, (r3, 12) + addi r0, 4 + tstnbz r1 + bf .L_string_tail + + ldw r1, (r3, 16) + addi r0, 4 + tstnbz r1 + bf .L_string_tail + + ldw r1, (r3, 20) + addi r0, 4 + tstnbz r1 + bf .L_string_tail + + ldw r1, (r3, 24) + addi r0, 4 + tstnbz r1 + bf .L_string_tail + + ldw r1, (r3, 28) + addi r0, 4 + tstnbz r1 + bf .L_string_tail + + addi r0, 4 + addi r3, 32 + br .L_start_addr_aligned + +.L_string_tail: +# ifdef __CSKYBE__ + xtrb0 r3, r1 + bez r3, .L_return + addi r0, 1 + xtrb1 r3, r1 + bez r3, .L_return + addi r0, 1 + xtrb2 r3, r1 + bez r3, .L_return + addi r0, 1 +# else + xtrb3 r3, r1 + bez r3, .L_return + addi r0, 1 + xtrb2 r3, r1 + bez r3, .L_return + addi r0, 1 + xtrb1 r3, r1 + bez r3, .L_return + addi r0, 1 +# endif /* !__CSKYBE__ */ + +.L_return: + rts + +.L_start_not_aligned: + sub r2, r2, r1 +.L_start_not_aligned_loop: + ldb r1, (r3) + PRE_BNEZAD (r2) + addi r3, 1 + bez r1, .L_return + addi r0, 1 + BNEZAD (r2, .L_start_not_aligned_loop) + br .L_start_addr_aligned +ENDPROC(strlen) |